Applications such as high temperature electrolysis and high temperature batteries include a sealed container to prevent reaction of active materials with air and moisture. Conventional designs attempt to seal the entire battery cell at the container level, thus requiring a high temperature seal. In addition to sealing the cell, the seal also electrically insulates the electrodes (e.g., the top and bottom halves of the container) such that conductive seal materials are prohibited. High temperature seals typically use glass or ceramic and are designed to maintain good sealing at a narrow range of operating temperatures. The glass or ceramic composition is usually tailored to match the thermal expansion of the container material at the targeted operating temperature. As a consequence, high temperature seals are generally limited in terms of thermal cycling.
A previous cell design utilizes low temperature seals by including a large thin flange that limits thermal conduction, as described in U.S. Pat. No. 3,419,432 (Hesson), which is incorporated herein by reference. However, this design has a large area for thermal conduction and is not thermally efficient. Moreover, as the cell of Hesson is scaled to larger sizes, its major thermal conduction area scales with its circumference.